Transmission jerks violently during upshifts after smaller pulley on kleemann SC
10-26-2012, 03:30 PM
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2005 E55 AMG
Transmission jerks violently during upshifts after smaller pulley on kleemann SC
I put a smaller pulley on my friends kleemann supercharged C55. While the car pulls freaking great, every time it upshifts the car hesitates and jerks violently and then continues to pull nicely. This happens on every shift.
It seems like it's a torque limiting factor but my ECU is already tuned by Eurocharged so my question is, has anyone else had this problem and what was the solution?
BTW- I'm not maxing out the MAF as I have a potentiometer installed to reduce the signal. I've had my suspicion that this could be a problem for the transmission but what other choice do I have?
It seems like it's a torque limiting factor but my ECU is already tuned by Eurocharged so my question is, has anyone else had this problem and what was the solution?
BTW- I'm not maxing out the MAF as I have a potentiometer installed to reduce the signal. I've had my suspicion that this could be a problem for the transmission but what other choice do I have?
10-26-2012, 04:23 PM
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I contacted Jerry but he says that I need a TCU reflash from him. My friend has already put thousands of dollars into this and I'm just wondering if there is any other way around this before dropping another $550+ on the TCU tune.
10-26-2012, 05:14 PM
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Oh, and their seem to be some kind of adaptation involved because if I disconnect the batter and reconnect it the problem goes away for about 4-5 wot runs and then it starts doing it again.
10-27-2012, 06:57 PM
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W203 slightly modified
The transmission control unit has hundreds of transmission profiles stored in it. It has a database of engine and transmission combinations.
When you change the power output of your engine there is a mismatch between the stored information and the new engine behaviour.
Recoding the transmission with a new combination could be one of two things. Either using a different entry from the database or writing a custom profile.
To use a different entry from the database you have to know which one to use. Since there are too many. But the tuners should have already worked through the options and figured out which path to take.
It may be as simple as telling the TCU it is in a different car than what it actually is.
When you change the power output of your engine there is a mismatch between the stored information and the new engine behaviour.
Recoding the transmission with a new combination could be one of two things. Either using a different entry from the database or writing a custom profile.
To use a different entry from the database you have to know which one to use. Since there are too many. But the tuners should have already worked through the options and figured out which path to take.
It may be as simple as telling the TCU it is in a different car than what it actually is.
